Analytical test systems, particularly those used in medical diagnostic applications, typically require routine quality control testing to assure that reported results are accurate. This is accomplished by running a sample of known analyte concentration in the test system and comparing the determined result with the known value for the sample. For test systems capable of performing assays for several analytes, each assay must be quality controlled routinely. Quality control samples with known values for multiple analytes are commercially available. In a multi-assay system, it often is possible to obtain all quality control results by running a single, multi-analyte, quality control sample.
In some multi-assay analyzers it may be desirable for commercial reasons to have the analyzer perform all available assays (y) on every sample but only allow reporting of results for a limited number (x) of the available assays. This is true typically in analyzers using a sealed reagent consumable such as an analyzer using a plastic centrifuge rotor having individual cells each containing a reagent for a different analytical test. Such an analyzer is sold by E. I. du Pont de Nemours and Company under the trademark Analyst. In this scenario, the analyzer operator could select which of the available assay results (up to x) he wishes to have reported. Consequently, even though all analytes are determined for a single sample, only a subset is reported. Unfortunately, there is no mechanism available to effect such result.
To obtain a quality control result for all assays on such a system, it would be necessary to provide plural rotors each having groups of reagents. The number of different rotors would be equal to the quotient of the number of assays available divided by the number of results reported with each run (y/x). Each group would contain control samples for the particular assays to be run for that group. This is undesirable because of increased cost and time required to prepare and run the number of determinations necessary to obtain a control result for each assay group. It would be desirable to provide a method of simultaneously providing a quality control assay for every analyte that may be tested in an analyzer and yet selectively provide test results when patient samples are run.